klkl

To Test POP3

telnet xxx.xxx.xxx.xxx 110 (xxx = mailserver)
+OK Hello there.
user USERNAME
+OK Password required.
pass PASSWORD
+OK logged in.
stat
+OK (Information about your mail)
quit
+OK Bye-bye.

Read the rest of this entry »

I’ve recently registered for accesss to the NHS’s dictionary of medicines and devices (dm+d). This was primarily to see what format the data was stored in and then to see if there was a way of utilising it in a cool webapp.

I downloaded the current release (its updated weekly) and unpacked the 5MB archive to reveal some XML and related files. Some of the files are huge (up to 32MB each and ~70MB in total) and there was no way a traditional program was going to mannage. I tried a few in fact and they all devastated my 2GB RAM and were generally unusable.

Time for a command line solution… VIM the open source text editor. Its extremely powerful and customisable but using it takes a little getting used to. VIM was able to open with only a slight delay and navigate these huge files. The next problem for me was being able to read them.

In theory it shouldn’t matter what indenting there is in an XML file as it doesn’t contain any data but I find its a lot easier to read the files if they’re ‘cleanly’ indented. I began wondering how I was going to solve the problem and thought of a few ideas… a script (PERL, PHP, shell, other…) but none of those came to fruition. After some searching I came across libxml.

You can download and compile from source if you wish but I decided to download a pre-built version from explain.com it was pretty good and another page I came across on entropy.ch explained how to use it within Vim to indent my files super quick.

Here’s what you do…

• To format type this sequence
  • :%!xmllint –format -
• Or mark the area visually and then type
  • !xmllint –format -

I’ve been doing some work involving an application that needs to query databases on separate servers however one of the servers will only accept mysql connections locally so the way round it is to forward connections from a port on one system to a port on a remote system. That way the connection to the remote database will appear as though it originated locally and be accepted.

To set up a tunneled connection you issue the following command on any client:

ssh -fNg -L 3307:127.0.0.1:3306 myuser@remotehost.com

The first command tells ssh to log in to remotehost.com as myuser, go into the background (-f) and not execute any remote command (-N), and set up port-forwarding (-L localport:localhost:remoteport ). In this case, we forward port 3307 on localhost to port 3306 on remotehost.com.

I’ve set up SMS Server Tools on my Mac Mini so that I can send text messages from my PC and I thought someone might be able to use the Applescript I’ve created or even suggest a better way of doing things.

If you’re not familiar with SMS Server Tools it’s a really great utility for sending text messages from your PC (I use the term generically) it works on (almost?) all UNIXs and Windows too. It works by having folders which it monitors for text message files and then sending them via the phone. It was very easy to set up just download the source, make, make install, edit the config file and away you go.

Read the rest of this entry »

A while ago I had an old Nokia N-95 plugged into a Gentoo box and I was using SMS Server Tools to send myself text message alerts. I got rid of that sim and so stopped using it. The phone has been sat in a drawer since then along with a couple of others.

I recently decided I wanted to set it all up again, this time on my Mac Mini. I was trying out different phones and settings but I couldn’t get the N95 or an old Motorola V series phone to do anything even after plugging them both in! Read the rest of this entry »

Last night I was working on determining how long a user had been logged into a PHP application but was having a problem with subtracting timestamps and this is how I solved it.

I was storing two timestamps (as a UNIX timestamp) in the database. One designating the date-time the user logged into the application and the other the date-time of the last activity the user performed. Because I was using UNIX timestamps, which are just the number of seconds sine the UNIX epoch, I subtracted one from the other and used that difference as the input to the PHP function date().

I couldn’t for the life of me work out why the date function was saying that I was logged in for an hour longer than I should have been and it was driving me crazy. It turns out that the reason was that my timezone locale setting in PHP is ‘Europe/London’ and that this causes the date function to adjust for British Summer Time (GMT + 1) thus when I used my timestamp difference in the date() function it translated the difference into a readable format but also added an extra hour.

The solution is to use gmdate() which is identical to the date() function except that the time returned is in Grenwich Mean Time format.

You may or may not know that Windows and Unix end lines in text files differently. Windows uses both a line feed and carriage return characters whereas Unix uses only the line feed character. This can be annoying if you’re working with documents on both systems interchangeably and you need to preserve a lot of indentation . One example for me is xml files I like writing them in a plain text editor because I cannot find an xml editor I get on with.

The solution is to use PERL:

• To convert Unix style line endings to Windows style
  • perl -p -e ’s/\n/\r\n/’ < unixfile.txt > winfile.txt
• To Convert Windows style line endings to Unix style
  • perl -p -e ’s/\r$//’ < winfile.txt > unixfile.txt

The use of single quotation marks in both command lines is important because it prevents the shell from trying to evaluate anything inside.

That’s it. A simple way to quicky convert line endings letting you get on with the job.

I dual boot a couple of my machines and whilst I was looking for a way to reapportion the size between two partitions I came across Gparted. It’s a Gnome based GUI for the GNU Parted program for creating, destroying, resizing, checking, and copying partitions, and the file systems on them.

What I really liked is there’s a linux livecd available so all you have to do is burn the disk image stick it in and aside from a few simple commands to boot the cd correctly it loads and starts Gparted.

Read the rest of this entry »

Ever needed to get rid of GRUB from a partition but didn’t know how? I managed to install GRUB onto my swap partition whilst setting up dual booting with Gentoo on a Mac Mini and faced this same problem. Using rEFIt it automatically detected GRUB on the partition and it showed up as a bootable option. I couldn’t be doing with that so I started looking for the solution. Loads of forum posts suggested fixmbr or fdisk but I didn’t want to replace GRUB I wanted shot of it. Anyway turns out the solution was to use dd.

# dd if=/dev/0 of=/dev/sdX bs=446 count=1

Where sdX is the partition to clean.

I’ve been looking for a way to start specific applications on specific desktops so things are more organized. For example I like to have my mail client (KMail) on the second desktop out of the way but there when I need it and I don’t like having to either start it in that desktop or move it to desktop two if I’ve had the application start automatically.

The utility to achieve this is kstart which is used to launch applications with special window properties such as to be full screen, below other windows or to not have an entry on the taskbar. The syntax is as follows;

user@host ~$ kstart [options] command

the specific argument (option) for my example is –desktop 2 and the whole command ‘kstart –desktop 2 kmail’ I’ve got mine set up as a .desktop shortcut in ~/kde/Autostart but you don’t have to have it there or use it in shortcuts it could be used in scripts or anywhere. I think this utility is great hence the post and hopefully it’ll take people less time than it did me to find the answer in future.